The prior art is replete with numerous attempts to make various tools from different materials. Tools for use in the fabrication of metals, ceramics, glasses, plastics, polymers, etc., are used primarily to shape the aforementioned materials in a predetermined manner. Thus, simply stated, a tool can be utilized to manufacture shaped ceramic, metal, glass and/or polymer or plastic products.
Many different types of tools currently exist for plastically deforming polymer or plastic materials. For example, tools for making shapes by blow molding, tools for making shapes by vacuum molding, compression molding tools, injection molding tools, tools against which materials are contacted or layed-up, tools for vacuum lay-ups, etc., are all examples of tools which are useful for making shaped plastics or polymers.
While the prior art contains many exemplary tools, numerous problems exist in tool design, as well as in the specific materials which are utilized for tools. For example, in the plastic or polymer molding industry, the materials utilized for tools suffer from various drawbacks, including short usable life times (e.g., the tools suffer from high wear either in localized areas or throughout the entire tool, thermal shock problems, etc. ), poor thermal conductivity, the relative inability to match the coefficient of thermal expansion of the tool to the formed product, unacceptably long lead time requirements for the preparation and manufacture of tools, high machining costs associated with the formation of tools (e.g., especially when the tools have an intricate or complex shape), the inability to control accurately and in a cost efficient manner the localized heating and/or cooling characteristics of the tool, large and sometimes quite heavy and awkwardly shaped tools, substantial difficulties in replicating master mold finishes, poor surface finishes, etc. The above-discussed problems are just a few of the problems facing manufacturers today, any one of which can result in high production costs and/or longer production times.
French Patent No. 7702248 relates to a method of producing a mold for use as part of a tool for shaping of mold or mold materials and having relatively high strength and heat resistance characteristics. According to the invention, there is formed a porous body of sinterable material in contact with a pattern to form a material-shaping surface of the body; the body when still in contact with the pattern surface is sintered and the sintered body is at least partially filled with infiltrating material having a melting point lower than that of the sintered body. The infiltrating step is effected in such manner that the pores of the surface of the sintered body in contact with the patterned surface are filled by infiltrating the material from the side of the body opposite to the pattern surface through to the surface which is formed by the patterned surface. The sintered porous body comprises a metal body. The infiltrating material also preferably comprises a metal, although non-metallic materials are also conceivable.
WO-A-81/02126 is directed to a method of producing an article and an article produced in a mold which defines the contour of the article. Specifically, an article as produced in a mold which defines the contours of the article, said article mainly consisting on the one hand of sinterable material which can be given a relatively easily shaped geometry, has the characteristics of forming a relatively porous body during sintering, such as a metal powder, which material is sintered in the mold, and on the other hand of a matrix consisting of a metal with a lower melting point than the sintering temperature for the sinterable material, said matrix metal infiltrating the porous body so that it fills in the pores of the sintered material, at least in the mold surface, and is molded by the mold before it is caused to solidify. The article also contains one or more cooling passages consisting of a metal tube with a melting point which is higher than the sintering temperature, the outside of the tube being metallically connected to the infiltrated matrix metal. In the method of producing the article, the mold is filled with powder or grains of the sinterable material, so that the tube is embedded in the sinterable material.
The present invention overcomes the difficulties referenced above as well as certain limitations of the prior art, and more, by providing novel materials for use as tools as well as new and improved tooling designs. Thus, the present invention results in tools having desirable mechanical properties which permit the repeated and reliable manufacture of complex shaped parts in large quantities, such parts potentially having quality characteristics heretofore being unachievable in a cost effective manner.